Sheet stackers with separator plates are known in the prior art. For instance, U.S. Pat. No. 3,969,993 shows a sheet stacker with a separator plate (and that patent is incorporated in this disclosure for purposes of reference as needed by anyone requiring further disclosure in the present case). That type of prior art stacker receives a stream of overlapped sheets and ultimately collects the stream and places its sheets into a final stack. In that process of stacking, a separator plate is used to intercept the initial formation of the stack, and a sheet counter operates the separator plate so that the final stack is composed of a determined and selected number of sheets controlled by the counter. That is, after the determined number of sheets have passed into the final stack on the stacker table or conveyor, than the separator plate is actuated so that it intercepts the remaining sheets headed toward the stack and separates those sheets from the initially formed stack so that the initially formed stack can be moved away and tied in its desired number of sheets, and then the entire process is repeated when the separator plate is withdrawn and the next stack is allowed to fully form on the stacker table.
Prior art U.S. Pat. No. 3,969,993 shows that its separator plate is controlled by mechanical means which includes a parallelogram type of linkage support for the plate so that the plate can move up and down along a straight line, as required. That is, the particular mounting of that separator plate is entirely mechanical means, and it requires the mounting arms and interconnecting support members, and, more particularly, it requires a spring and connecting elements for the return or upward movement of the separator plate.
The present invention improves upon the prior art in that it does not require the cumbersome, costly, and generally mechanical mounting for the separator plate, particularly including the mechanical elements required for returning the plate to its up position, namely, the springs, fluid-actuated cylinders, hydraulic dampers, or the like. Therefore, the present invention simplifies the prior art in the mounting and control for the up and down movement of the separator plate.
Specifically, the present invention provides one driving member for moving the stacker table and the separator plate in their downward movements, and it provides one driving member for moving the stacker table and the separator plate in their upward movements. A clutch is respectively used with the stacker table and with the separator plate so that they move downward and upward alternately, in the desired manner.
In broad concepts, the present invention improves upon the prior art in providing a lower cost and more simplified structure for a stacker with a separator plate, and the structure of the present invention is more reliable in its action in that it has fewer mechanical parts.
Other objects and advantages will become apparent upon reading the following description.